You want the yeast to grow some in the beer to give the beer the character that the yeast is supposed to give the beer. The less yeast character you want, the more yeast you can get away with pitching. Too much yeast would theoretically give you a beer lacking something in the flavor, but a lot of yeast is desirable if you want the beer to be "clean" tasting.

That said, it's pretty hard to get enough yeast to pitch too much. The time when homebrewers MAY come close to pitching too much is when the ferment a new beer with the entire yeast cake of a previous beer.

The best thing to do is go to mrmalty.com and calculate how much yeast is the right amount of yeast to use and come as close to that as possible.

The reason I'm asking is back some time ago I started to get this on top of my beer. (see this post http://www.beertools.com/forum/viewtopic.php?t=2117 ) Now this all started when I got new yeast. The yeast I had was close to the exp date. Now the yeast I'm getting now is very fresh.

Now I started out with one pack of 6gr dry yeast in a 5gal batch. I upped the batch to about 6gal and started to have fermentation problems. I found that I was under pitching the amount of yeast I needed. I used 2 packects of yeast and the beer I was making fermentated fine. Now that was with the old yeast that was close to the exp date. Now I'm making 11.5gal batches and I used 4 packets of yeast. Or 2 depending on the yeast I use. Now the with the info slothrob gave me I'm pitching to much yeast for the beer I'm making. Now I don't get the problem with the odd growth on top of my beer all the time. Now with the info from the Mr Malty's Pitching Rate Calculator. The beer that I was not getting the growth on was the beer that I pitched the right amount of yeast according to Mr Malty's Pitching Rate Calculator.

So What I'm asking is will to much yeast pitched make the yeast form a new yeast colonies on top of my beer?

Sometimes the krasuen on the top of the ferment will dry out and become crusty. Then thru time the fermenting wort from below will "crack thru" the top layer and begin to seep thru it causing this weird looking krasuen...
If the beer is good...don't fix it!!

Sometimes the krasuen on the top of the ferment will dry out and become crusty. Then thru time the fermenting wort from below will "crack thru" the top layer and begin to seep thru it causing this weird looking krasuen...If the beer is good...don't fix it!!

Good luck!

That is the calculator I used. What is bugging me is this never happed before and I what to know what it is and why i'm getting it.

I agree, Mr. Malty is an excellent site for yeast calculator. I used this before I started using White Lab yeast vials. The vials are liquid and are extremely easy to use. Just let it set out at room temperature for 3 hours before pitching, shake and pour into the wort. I have been very happy with the results.

hansolo wrote:I agree, Mr. Malty is an excellent site for yeast calculator. I used this before I started using White Lab yeast vials. The vials are liquid and are extremely easy to use. Just let it set out at room temperature for 3 hours before pitching, shake and pour into the wort. I have been very happy with the results.

You don't even have to warm them up first, the yeast will work fine right from the fridge. Unfortunately, it's only really the right amount of yeast for a ~1.035 beer. For a 1.050+ beer you'll be underpitching by about 1/2 or more. So, even though you'll get by most times, you'd be better served by making a starter even from the WhiteLabs vials and Wyeast Activator packs.

slothrob wrote:You don't even have to warm them up first, the yeast will work fine right from the fridge. Unfortunately, it's only really the right amount of yeast for a ~1.035 beer. For a 1.050+ beer you'll be underpitching by about 1/2 or more. So, even though you'll get by most times, you'd be better served by making a starter even from the WhiteLabs vials and Wyeast Activator packs.

I have to disagree with you there, just a little. For a 5 gallon batch that we have been brewing, the Whitelab Vials work fine with our Irish Stout up to 1.055, so far but if we were to add more malts or fermentables to the recipe, I would probably just add another vial. I haven't gotten to the point to make yeast starters yet but it will be something I will be doing soon when we start brewing 10 gallons.

Yes, I tried to make that point, but maybe I wasn't clear. A single vial will usually do for a 1.050 beer. It is less than optimal, though. You will have higher ester levels and a greater risk of off flavors like diacetyl. You'll also increase your risk of an incomplete fermentation.

If you use the MrMalty pitching calculator, you'll see that nearly twice the number of cells in one of these packages is the recommended pitching rate.

If you're happy with the result, there''s no need to change, but many brewers find their beers improve after using starters to optimize their pitching rate.